Electrochemical wastewater and soil treatments are exciting set of technologies that has been well-studied over the recent years as one of the most-effective remediation techniques for the removal of hazardous pollutants from liquids effluents and soil. The main requirement of these technologies is electricity and their sustainability can be largely improved if they are powered by renewable energy sources. Likewise, this green energy powering can help to apply these technologies in remote areas, such as rural communities in developing countries, where no electricity grid is available. This review presents a comprehensive discussion on fundamental concepts and applications of renewable energy driven electrochemical technologies for treating hazardous pollutants in wastewater and contaminated soils. In the first section, the fundamentals of different electrochemical remediation technologies are presented, whereas the next two sections focused on the most applied technologies for powering these electrochemical devices: the solar photovoltaic (PV) (Section 3) and the wind turbines (Section 4). After that, the non-near future is faced with the study of the principles of biomass energy production and how bioelectrochemical systems are starting to be evaluated for powering electrochemical technologies (Section 5). Then, new approaches in the renewable energy driven electrochemical technologies such as triboelectric nanogenerators and photocatalytic fuel cells are described in Section 6. The last section focused on the challenges expected for the near future, describing the most promising storage system and evaluating the scale-up, environmental and economic concerns of the technologies studied in this work.

Renewable energies driven electrochemical wastewater/soil decontamination technologies: A critical review of fundamental concepts and applications

The use of renewable energies driving electrochemical technologies for environmental applications

Electrode dependent anaerobic ammonium oxidation in microbial fuel cell integrated hybrid constructed wetlands: A new process

The main issues with mainstream anammox application are loss of bacterial activity by low temperatures and by a high organic content of wastewater. We demonstrate a novel switching method between s...

Mainstream-sidestream wastewater switching promotes anammox nitrogen removal rate in organic-rich, low-temperature streams.

Review on electrochemical system for landfill leachate treatment: Performance, mechanism, application, shortcoming, and improvement scheme.

Power generation and pollutants removal from landfill leachate in microbial fuel cell: Variation and influence of anodic microbiomes.

In natural environments, plants frequently interact with both heterospecific and conspecific neighbors. The intensity of belowground plant interaction with neighboring species commonly varies with the availability of soil nutrients in the habitats. According to classical ecological theory, competition between conspecific neighbors may be more severe than competition between unrelated species due to the similar nutrient requirements of close relatives, especially when nutrients are scarce in the habitat. However, many recent studies have shown the opposite pattern, and suggested an alternative mechanism based on species recognition. Taking Zoysia sinica as the focal species, we conducted a controlled experiment to test the results of intraspecific and interspecific interactions among three clonal species Zoysia sinica, Zoysia japonica and Alternanthera philoxeroides, which represent a conspecific, a close relative and a distant relative of the focal species, respectively, and at different root treatments (no separation NS, clone separation CS and ramet separation RS) and two nutrient levels. The results showed that Z. sinica recognized conspecific plants in the NS and CS treatments, and did not show above or belowground competition with these. The performance of the focal plant (Z. sinica) was better when it was grown with a conspecific neighbor as compared to all other types of neighbors. In all root separation treatments, the competition was more intense when Z. sinica grew with a close relative (Z. japonica) than when growing with a distant relative (A. philoxeroides). Generally, competition between plants was more intense at the high nutrient level than at the low nutrient level, suggesting that both soil nutrients and a species recognition mechanism play a significant role for the intra‐ and interspecific interaction and fitness of these three neighboring clonal species.

Effect of soil nutrients, neighbor identities and root separation types on intra‐ and interspecific interaction among three clonal plant species

Relative costs and benefits of clonal integration of Zoysia japonica under various N:P ratios

Plants frequently interrelate with their neighbors at different levels of genetic relatedness in close contiguity due to sessile in nature and limited seed dispersal. Niche differentiation may diminish competition among the neighboring plants, and the interactions among neighbors may also be influenced according to their identity or genetic relatedness. However, it is still unclear how interactions among individuals at different levels of genetic relatedness can be affected by different nutrient and planting density conditions. To answer this question, we conducted a greenhouse experiment. The materials were three genotypes of Setaria italica, i.e., Special early no.1 (focal plant), GT 35-1 (neighbor) and Golden valley 808 (neighbor), and Triticum aestivum (neighbor). According to the affinity level, plants were grown with different combinations, such as close kin (A1A1), far kin (A1A2), non-kin (A1A3), and stranger group (A1B). Planting density in the pots set either short distance or long distance with low and high of two levels of nutrient supply. Results showed spike diameter, spike length and aboveground biomass significantly higher in the close-kin treatment, but simultaneously root competition was more intense at short planting distance, under the condition of low and high nutrient levels in close kin treatment as compared to other interactions. We concluded that interactions among individuals of Setaria italica at different nutrient conditions influenced by both neighbor's identity and planting density.

Syed Wajahat Husain Jaafry

Papers

Power generation and pollutants removal from landfill leachate in microbial fuel cell: Variation and influence of anodic microbiomes.

Effect of soil nutrients, neighbor identities and root separation types on intra‐ and interspecific interaction among three clonal plant species

Relative costs and benefits of clonal integration of Zoysia japonica under various N:P ratios

Interactions among individuals of Setaria Italica at different levels of genetic relatedness under different nutrient and planting density conditions

Interactions Among the Plants with Different Neighbor Identities and Plant Communication (A Review)